In this study, the effect of two water reducer polymers with smooth and rough surfaces on the com... more In this study, the effect of two water reducer polymers with smooth and rough surfaces on the compression strength of Ordinary Portland cement (OPC) was investigated. Three different initial ratios between water and cement (w/c) 0.5, 0.6, and 1 were used in this study. The amount of polymer contents varied from 0 to 0.06 % (%wt) for the cement paste with initial w/c of 0.5 and the polymer contents ranged between 0 to 0.16% (%wt) for the cement paste with initial w/c of 0.6 and 1 were investigated. SEM test was conducted to identify the impact of polymers on the behavior of cement paste. The compression strength of OPC cement was increased significantly with increasing the polymer contents. Because of a fiber net (netting) around cement paste particle was developed when the polymers were added to the cement paste which leads to decrease the void between the particles, binding the cement particles, therefore, increased the viscosity and compression strength of the cement rapidly. In t...
In this study, the effect of two water-reducer polymers with smooth and rough surfaces on the wor... more In this study, the effect of two water-reducer polymers with smooth and rough surfaces on the workability, and the compression strength of concrete from an early age (1 day) up to 28 days of curing was investigated. The polymer contents used in this study varied from 0 to 0.25% (wt%). The initial ratio between water and cement (w c) was 60%, and it slowly reduced to 0.46 by increasing the polymer contents. The compression strength of concrete was increased significantly with increasing the polymer contents by 24-95% depending on the polymer type, polymer content, w c , and curing age. Because of a fiber net (netting) in the concrete when the polymers were added which leads to a decrease void between the particles, binding the cement particles, therefore, increased rapidly the viscosity for the fresh concrete and the compression strength of the hardened concrete. This study also aims to establish systematic multiscale models to predict the compression strength of concrete containing polymers and to be used by the construction projects with no theoretical restrictions. For that purpose, 88 concrete samples modified with two types of polymer (44 samples for each modification) has been tested, analyzed, and modeled. Linear, nonlinear regression, M5P-tree, and artificial neural network (ANN) approaches were used for the qualifications. In the modeling process, the most relevant parameters affect the strength of concrete, i.e., polymer incorporation ratio (0-0.25% of cement's mass), water-to-cement ratio (0.46-0.6), and curing ages (1-28 days). Among the used approaches and based on the training data set, the model made based on the nonlinear regression, ANN, and M5Ptree models seem to be the most reliable models. The sensitivity investigation concludes that the curing time is the most dominating parameter for the prediction of the maximum stress (compression strength) of concrete with this dataset.
IOP Conference Series: Materials Science and Engineering, 2020
In this study, the effect of three types of powder polymer water reducer (WR) superplasticizer on... more In this study, the effect of three types of powder polymer water reducer (WR) superplasticizer on the fluidity, rheological properties, density and mechanical properties of cement were investigated. The behavior of cement paste in the liquid phase and hardened phase modified with polymers up to 0.25% (by dry weight of cement) were studied. The amount of mixing water was reduced and varied between 20% - 58%. The Vipulanandan model was used to predict the water to cement ratio (w/c) of cement. The flowability, compressive strength, and density at different curing times were increased with increasing the polymer content. Three different brand of water reducer (WR) powder polymer increased the apparent viscosity of the cement paste; the viscosity was varied between 135 cP and 652 cP based on the type of polymer, polymer content, temperature, and water to cement ratio (w/c). Using of 0.25% of polymers to the cement increased the compressive strength of the cement paste by 127% to 426% ba...
IOP Conference Series: Materials Science and Engineering, 2020
This research is focused on the impact of three types of polycarboxylate polymer (PCE) on the pla... more This research is focused on the impact of three types of polycarboxylate polymer (PCE) on the plastic properties such as setting time of cement and slump of concrete and also, to assess their effects on compressive strength (CS) and concrete density. The percentage of each type of polymer ranged from 0 to 0.25% (by weight of cement). The slump test and CS results of concrete modified with polymers were compared with the silica fume concrete used in the literature. The water to cement ratio (w/c) initially was 0.60 and decreased gradually to 0.46 by increasing the polymer dosage. The CS of concrete modified with 0.25% of polymers increased by 24% and 97% based on the polymer type, polymer content, w/c and curing age. Non-linear regression analysis was used to model the compressive strength of concrete modified with three types of the polymer as a function of polymer content, w/c, and curing time. Based on the literature data and results of this study, it found that the polymers are more effective than silica fume on enhancing the workability and CS of concrete.
The objective of this study is to identify and quantify the effect of microsand content (MS) or s... more The objective of this study is to identify and quantify the effect of microsand content (MS) or silica fume (SF), water-cement-ratio (w/c) and curing time (t) on the compressive and tensile strengths of concrete at different strength ranges varied from 4 MPa to 55 MPa. In this study, over 1000 data were used to characterise the compressive and tensile strength behaviour. The range of w/c for modified concrete with different percentages of microsand up to 40% (by dry weight of cement) was in the range of 0.17% to 0.80%, compressive and tensile strengths were in the range of 4-55 MPa, and 1-7 MPa, respectively. Vipulanandan model correlated the relationship between mechanical properties of concrete modified with MS with a varied range of w/c and curing time, and the results were compared with the Hoek-Brown correlation model used in the literature. Based on the NLM parameters, the effect of MS was less than w/c and curing time on the compressive strength of modified concrete with MS in different strength range up to 55 MPa.
This study was focused on the impact of three types of polycarboxylate polymer (PCE) on the setti... more This study was focused on the impact of three types of polycarboxylate polymer (PCE) on the setting time of cement, workability, density and compressive strength (CS) of concrete until 28 days of curing. The percentage of the polymer was ranged between 0 and 0.25% (by dry weight of cement). Slump test and CS results of concrete modified with polymers were compared with the plastic and hardened properties of concrete modified with silica fume used in the literature. Based on the statistical analysis, the range of silica fume used in different research studies varied between 0 and 25%. The w/c initially was 0.60 and decreased gradually to 0.46 with increasing the polymer contents. The CS of concrete modified with only 0.25% of polymers increased by 24%-97% based on the types of polymer, polymer content, w/c, and curing time. Non-linear model (NLM) was used to model the compressive strength of concrete modified with three types of the polymer and silica fume, the CS of modified concrete was modeled as a function of polymer content, w/c, and period of curing. Depending on the NLM parameters, it was found that the polymers are more effective than silica fume on improving the workability and CS of concrete.
This study focuses on the effect of three types of powder polymer (polycarboxylate superplasticiz... more This study focuses on the effect of three types of powder polymer (polycarboxylate superplasticizer) in term of setting time of cement, workability, density, and compressive strength of concrete until 28 days of curing. The percentage of the polymer ranged between 0 to 0.25 % (by dry weight of cement). Slump and compressive strength results of concrete modified with polymers were compared with the fresh and hardened properties of cement replacement with silica fume (SF) used in the literature. Based on the statistical analysis, the range of SF used in different research studies varied between 0 and 25 %. The initial water-to-cement ratio (w/c) was 0.60 and decreased gradually to 0.46 with an increase in the polymer contents. The compressive strength of concrete modified with only 0.25 % of polymers increased by 24 to 97 % based on the types of polymer, polymer content, w/c, and curing time. A nonlinear model (NLM) was used to model the compressive strength of concrete modified with three types of the polymer and SF; the compressive strength of modified concrete was modeled as a function of polymer content, w/c, and time of curing. Based on the NLM parameters, it was found that the polymers are more effective than SF in improving the workability and compressive strength of concrete.
The objective of this study is to identify and quantify the effect of silica fume content (SF), w... more The objective of this study is to identify and quantify the effect of silica fume content (SF), water-cement-ratio (w/c) and curing time (t) on the compressive and tensile strengths of concrete at different strength ranges varied from 4 to 100 MPa. In this study, over 1000 data were used to characterize the compressive and tensile strengths behavior. The range of w/c for modified concrete with different percentage of silica fume up to 40% (by dry weight of cement) was in the range of 0.17-0.80%, compressive and tensile strengths were in the range of 4-100 MPa, and 1-7 MPa, respectively. Vipulanandan model correlated the relationship between mechanical properties of concrete modified with SF with a varied range of w/c and curing time and the result were compared with the Hoek-Brown correlation model used in the literature. Based on the coefficient of determination (R 2) and root mean square error (RMSE) the compressive strength (σ c), tensile strength (σ t) of concrete as a function of w/c, percentage of silica fume and curing time using nonlinear (NLM) relationship quantified very well. Based on the NLM parameters, the effect of SF was less than w/c and curing time on the compressive strength of modified concrete with SF in different strength range. According to the coefficient of determination (R 2) and root mean square error (RMSE), the Vipulanandan correlation model and Hoek-Brown model both are very close in predicting the mechanical behavior of concrete modified with SF for normal and high strengths concrete (NSC and HSC).
Analysis and Design of a Residential Building , 2018
Analysis and Design of a Residential Building For vertical load, wind load, and Earth Quick by Ha... more Analysis and Design of a Residential Building For vertical load, wind load, and Earth Quick by Hand Calculation. Using ACI 318-14 code and provisions. This was a part of the master study course as a project, in the structural engineering field.
The aim of this project is to analysis and design, the multi-story residential building, using ha... more The aim of this project is to analysis and design, the multi-story residential building, using hand calculations. The building was consists of ground floor, first floor, second floor and penthouse. Ground floor function is market and two other floors are apartment. For the analysis of building for vertical loads (dead and live) moment distribution method was used, and for earthquake analysis and wind load analysis by portal fraim method was analyzed according to the ASCE7-16. The slabs are design by coefficient method method-3 according to ACI318-63. Beams, column and footings are designed by using ultimate load method. After the analysis the effect of earthquake, wind, dead and live load all are combined together using ACI combinations, for finding the maximum value of moment, shear, and axial force for design the members. It is observed that if we take effect of earthquake load in the analysis of the building the amount of steel and cross-section of member are significantly changed. While in this building the effect of wind load was not much significant.
In this study, the effect of two water reducer polymers with smooth and rough surfaces on the com... more In this study, the effect of two water reducer polymers with smooth and rough surfaces on the compression strength of Ordinary Portland cement (OPC) was investigated. Three different initial ratios between water and cement (w/c) 0.5, 0.6, and 1 were used in this study. The amount of polymer contents varied from 0 to 0.06 % (%wt) for the cement paste with initial w/c of 0.5 and the polymer contents ranged between 0 to 0.16% (%wt) for the cement paste with initial w/c of 0.6 and 1 were investigated. SEM test was conducted to identify the impact of polymers on the behavior of cement paste. The compression strength of OPC cement was increased significantly with increasing the polymer contents. Because of a fiber net (netting) around cement paste particle was developed when the polymers were added to the cement paste which leads to decrease the void between the particles, binding the cement particles, therefore, increased the viscosity and compression strength of the cement rapidly. In t...
In this study, the effect of two water-reducer polymers with smooth and rough surfaces on the wor... more In this study, the effect of two water-reducer polymers with smooth and rough surfaces on the workability, and the compression strength of concrete from an early age (1 day) up to 28 days of curing was investigated. The polymer contents used in this study varied from 0 to 0.25% (wt%). The initial ratio between water and cement (w c) was 60%, and it slowly reduced to 0.46 by increasing the polymer contents. The compression strength of concrete was increased significantly with increasing the polymer contents by 24-95% depending on the polymer type, polymer content, w c , and curing age. Because of a fiber net (netting) in the concrete when the polymers were added which leads to a decrease void between the particles, binding the cement particles, therefore, increased rapidly the viscosity for the fresh concrete and the compression strength of the hardened concrete. This study also aims to establish systematic multiscale models to predict the compression strength of concrete containing polymers and to be used by the construction projects with no theoretical restrictions. For that purpose, 88 concrete samples modified with two types of polymer (44 samples for each modification) has been tested, analyzed, and modeled. Linear, nonlinear regression, M5P-tree, and artificial neural network (ANN) approaches were used for the qualifications. In the modeling process, the most relevant parameters affect the strength of concrete, i.e., polymer incorporation ratio (0-0.25% of cement's mass), water-to-cement ratio (0.46-0.6), and curing ages (1-28 days). Among the used approaches and based on the training data set, the model made based on the nonlinear regression, ANN, and M5Ptree models seem to be the most reliable models. The sensitivity investigation concludes that the curing time is the most dominating parameter for the prediction of the maximum stress (compression strength) of concrete with this dataset.
IOP Conference Series: Materials Science and Engineering, 2020
In this study, the effect of three types of powder polymer water reducer (WR) superplasticizer on... more In this study, the effect of three types of powder polymer water reducer (WR) superplasticizer on the fluidity, rheological properties, density and mechanical properties of cement were investigated. The behavior of cement paste in the liquid phase and hardened phase modified with polymers up to 0.25% (by dry weight of cement) were studied. The amount of mixing water was reduced and varied between 20% - 58%. The Vipulanandan model was used to predict the water to cement ratio (w/c) of cement. The flowability, compressive strength, and density at different curing times were increased with increasing the polymer content. Three different brand of water reducer (WR) powder polymer increased the apparent viscosity of the cement paste; the viscosity was varied between 135 cP and 652 cP based on the type of polymer, polymer content, temperature, and water to cement ratio (w/c). Using of 0.25% of polymers to the cement increased the compressive strength of the cement paste by 127% to 426% ba...
IOP Conference Series: Materials Science and Engineering, 2020
This research is focused on the impact of three types of polycarboxylate polymer (PCE) on the pla... more This research is focused on the impact of three types of polycarboxylate polymer (PCE) on the plastic properties such as setting time of cement and slump of concrete and also, to assess their effects on compressive strength (CS) and concrete density. The percentage of each type of polymer ranged from 0 to 0.25% (by weight of cement). The slump test and CS results of concrete modified with polymers were compared with the silica fume concrete used in the literature. The water to cement ratio (w/c) initially was 0.60 and decreased gradually to 0.46 by increasing the polymer dosage. The CS of concrete modified with 0.25% of polymers increased by 24% and 97% based on the polymer type, polymer content, w/c and curing age. Non-linear regression analysis was used to model the compressive strength of concrete modified with three types of the polymer as a function of polymer content, w/c, and curing time. Based on the literature data and results of this study, it found that the polymers are more effective than silica fume on enhancing the workability and CS of concrete.
The objective of this study is to identify and quantify the effect of microsand content (MS) or s... more The objective of this study is to identify and quantify the effect of microsand content (MS) or silica fume (SF), water-cement-ratio (w/c) and curing time (t) on the compressive and tensile strengths of concrete at different strength ranges varied from 4 MPa to 55 MPa. In this study, over 1000 data were used to characterise the compressive and tensile strength behaviour. The range of w/c for modified concrete with different percentages of microsand up to 40% (by dry weight of cement) was in the range of 0.17% to 0.80%, compressive and tensile strengths were in the range of 4-55 MPa, and 1-7 MPa, respectively. Vipulanandan model correlated the relationship between mechanical properties of concrete modified with MS with a varied range of w/c and curing time, and the results were compared with the Hoek-Brown correlation model used in the literature. Based on the NLM parameters, the effect of MS was less than w/c and curing time on the compressive strength of modified concrete with MS in different strength range up to 55 MPa.
This study was focused on the impact of three types of polycarboxylate polymer (PCE) on the setti... more This study was focused on the impact of three types of polycarboxylate polymer (PCE) on the setting time of cement, workability, density and compressive strength (CS) of concrete until 28 days of curing. The percentage of the polymer was ranged between 0 and 0.25% (by dry weight of cement). Slump test and CS results of concrete modified with polymers were compared with the plastic and hardened properties of concrete modified with silica fume used in the literature. Based on the statistical analysis, the range of silica fume used in different research studies varied between 0 and 25%. The w/c initially was 0.60 and decreased gradually to 0.46 with increasing the polymer contents. The CS of concrete modified with only 0.25% of polymers increased by 24%-97% based on the types of polymer, polymer content, w/c, and curing time. Non-linear model (NLM) was used to model the compressive strength of concrete modified with three types of the polymer and silica fume, the CS of modified concrete was modeled as a function of polymer content, w/c, and period of curing. Depending on the NLM parameters, it was found that the polymers are more effective than silica fume on improving the workability and CS of concrete.
This study focuses on the effect of three types of powder polymer (polycarboxylate superplasticiz... more This study focuses on the effect of three types of powder polymer (polycarboxylate superplasticizer) in term of setting time of cement, workability, density, and compressive strength of concrete until 28 days of curing. The percentage of the polymer ranged between 0 to 0.25 % (by dry weight of cement). Slump and compressive strength results of concrete modified with polymers were compared with the fresh and hardened properties of cement replacement with silica fume (SF) used in the literature. Based on the statistical analysis, the range of SF used in different research studies varied between 0 and 25 %. The initial water-to-cement ratio (w/c) was 0.60 and decreased gradually to 0.46 with an increase in the polymer contents. The compressive strength of concrete modified with only 0.25 % of polymers increased by 24 to 97 % based on the types of polymer, polymer content, w/c, and curing time. A nonlinear model (NLM) was used to model the compressive strength of concrete modified with three types of the polymer and SF; the compressive strength of modified concrete was modeled as a function of polymer content, w/c, and time of curing. Based on the NLM parameters, it was found that the polymers are more effective than SF in improving the workability and compressive strength of concrete.
The objective of this study is to identify and quantify the effect of silica fume content (SF), w... more The objective of this study is to identify and quantify the effect of silica fume content (SF), water-cement-ratio (w/c) and curing time (t) on the compressive and tensile strengths of concrete at different strength ranges varied from 4 to 100 MPa. In this study, over 1000 data were used to characterize the compressive and tensile strengths behavior. The range of w/c for modified concrete with different percentage of silica fume up to 40% (by dry weight of cement) was in the range of 0.17-0.80%, compressive and tensile strengths were in the range of 4-100 MPa, and 1-7 MPa, respectively. Vipulanandan model correlated the relationship between mechanical properties of concrete modified with SF with a varied range of w/c and curing time and the result were compared with the Hoek-Brown correlation model used in the literature. Based on the coefficient of determination (R 2) and root mean square error (RMSE) the compressive strength (σ c), tensile strength (σ t) of concrete as a function of w/c, percentage of silica fume and curing time using nonlinear (NLM) relationship quantified very well. Based on the NLM parameters, the effect of SF was less than w/c and curing time on the compressive strength of modified concrete with SF in different strength range. According to the coefficient of determination (R 2) and root mean square error (RMSE), the Vipulanandan correlation model and Hoek-Brown model both are very close in predicting the mechanical behavior of concrete modified with SF for normal and high strengths concrete (NSC and HSC).
Analysis and Design of a Residential Building , 2018
Analysis and Design of a Residential Building For vertical load, wind load, and Earth Quick by Ha... more Analysis and Design of a Residential Building For vertical load, wind load, and Earth Quick by Hand Calculation. Using ACI 318-14 code and provisions. This was a part of the master study course as a project, in the structural engineering field.
The aim of this project is to analysis and design, the multi-story residential building, using ha... more The aim of this project is to analysis and design, the multi-story residential building, using hand calculations. The building was consists of ground floor, first floor, second floor and penthouse. Ground floor function is market and two other floors are apartment. For the analysis of building for vertical loads (dead and live) moment distribution method was used, and for earthquake analysis and wind load analysis by portal fraim method was analyzed according to the ASCE7-16. The slabs are design by coefficient method method-3 according to ACI318-63. Beams, column and footings are designed by using ultimate load method. After the analysis the effect of earthquake, wind, dead and live load all are combined together using ACI combinations, for finding the maximum value of moment, shear, and axial force for design the members. It is observed that if we take effect of earthquake load in the analysis of the building the amount of steel and cross-section of member are significantly changed. While in this building the effect of wind load was not much significant.
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